I start by telling the students that I want to challenge them today. I want to see how many different ways they can fill some of the pattern blocks that we have been working with. I first have each of the students grab a blue rhombus from the pile of shapes. I then ask if anyone can tell me the name of the shape? I then ask if anyone can make this shape using other pattern blocks? Once they do, I want them to put their thumb on their chin to show me they are ready. I ask students to share the way (there is only 1 in this case) they were able to replicate the rhombus. I then record the combination (of two green triangles) on a piece of poster paper (CCSS.MATH.CONTENT.1.G.A.2). I continue this same routine for the trapezoid and the hexagon. Each time I am recording the different ways that each shape can be made. The students are "making sense of quantities (in this case number of shapes) and their relationships in problem situations (CCSS.Math.Practice.MP2)."

When I am done, I will end the discussion with some questions about the hexagon:

1. What do you think is the most blocks that you can use to make a hexagon?

The goal of center time is for the students to work with pattern blocks in a variety of ways. These activities will be available over the next few lessons Students can choose which activity he/she wants to do based in interest. The students are using pattern blocks as a mathematical tool, to solve designs and fill in outlines, throughout all of these activities (CCSS.Math.Practice.MP5)

2. Fun With Pattern Blocks: This activity was introduced in a previous lesson. You will have to print the Fun With Pattern Block Template and create 4 new designs. Again read through the description, in the link above, to learn how to do this. As you create each sheet label it a new number. There is a spot to do this near the top of the template.

3. How Many Pattern Blocks?: This activity was introduced in a previous lesson.

Students should complete the practice sheet (see section resource). The equations on this sheet require the students solve for unknown addends (CCSS.Math.Content.1.OA.D.8). I have included a photo (in lesson resource) of how I adapted the activity for one child. I left a container of cubes on her table and didn't say anything about them. She chose to use them to help her with the addition equations. There is also a picture of a completed sheet by a student.

Big Idea:
The number line is a tool students will use in math from Kindergarten all the way through high school! This lesson has students explore how to model missing addend/subtrahend using the number line.